This is tricky, because it involves both the snap setting in the track view, and the snap setting in the PRV.
To reproduce
1) Open project with simple instrument tracks, and view the tracks in the PRV.
2) In PRV -> View, select Grid Resolution -> Follow Snap Settings
3) The problem: Changing the snap setting in the PRV (top right) has no affect on the grid resolution.
Now, to reproduce some quirky behavior:
1) Change snap setting in PRV, e.g. to 1/32. Note that it has no effect on grid resolution. Zoom in to confirm.
2) Change snap setting in track view, to anything, e.g. Whole. Note that the grid resolution in the PRV changes to the correct setting for the PRV, e.g. 1/32.
This means: Changes to PRV snap settings don't affect grid resolution until you change the snap setting (to any value) in the track view.
It looks like the refresh to the PRV is missing after you change the PRV snap setting, but the refresh finally gets triggered when you change the snap setting in the track view.
Thanks!